// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_BUFFER_TRACKER_H_
#define MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_BUFFER_TRACKER_H_

#include <memory>

#include "base/synchronization/lock.h"
#include "media/capture/video/video_capture_buffer_handle.h"
#include "media/capture/video_capture_types.h"
#include "mojo/public/cpp/system/buffer.h"

namespace media {

// Keeps track of the state of a given mappable resource. Each
// VideoCaptureBufferTracker carries indication of pixel format and storage
// type. This is a base class for implementations using different kinds of
// storage.
class CAPTURE_EXPORT VideoCaptureBufferTracker {
public:
    VideoCaptureBufferTracker()
        : max_pixel_count_(0)
        , held_by_producer_(false)
        , consumer_hold_count_(0)
        , frame_feedback_id_(0)
    {
    }
    virtual bool Init(const gfx::Size& dimensions,
        media::VideoPixelFormat format,
        media::VideoPixelStorage storage_type,
        base::Lock* lock)
        = 0;
    virtual ~VideoCaptureBufferTracker() {};

    const gfx::Size& dimensions() const { return dimensions_; }
    void set_dimensions(const gfx::Size& dim) { dimensions_ = dim; }
    size_t max_pixel_count() const { return max_pixel_count_; }
    void set_max_pixel_count(size_t count) { max_pixel_count_ = count; }
    media::VideoPixelFormat pixel_format() const { return pixel_format_; }
    void set_pixel_format(media::VideoPixelFormat format)
    {
        pixel_format_ = format;
    }
    media::VideoPixelStorage storage_type() const { return storage_type_; }
    void set_storage_type(media::VideoPixelStorage storage_type)
    {
        storage_type_ = storage_type;
    }
    bool held_by_producer() const { return held_by_producer_; }
    void set_held_by_producer(bool value) { held_by_producer_ = value; }
    int consumer_hold_count() const { return consumer_hold_count_; }
    void set_consumer_hold_count(int value) { consumer_hold_count_ = value; }
    void set_frame_feedback_id(int value) { frame_feedback_id_ = value; }
    int frame_feedback_id() { return frame_feedback_id_; }

    virtual std::unique_ptr<VideoCaptureBufferHandle> GetMemoryMappedAccess() = 0;
    virtual mojo::ScopedSharedBufferHandle GetHandleForTransit() = 0;
    virtual base::SharedMemoryHandle
    GetNonOwnedSharedMemoryHandleForLegacyIPC()
        = 0;

private:
    // |dimensions_| may change as a VideoCaptureBufferTracker is re-used, but
    // |max_pixel_count_|, |pixel_format_|, and |storage_type_| are set once for
    // the lifetime of a VideoCaptureBufferTracker.
    gfx::Size dimensions_;
    size_t max_pixel_count_;
    media::VideoPixelFormat pixel_format_;
    media::VideoPixelStorage storage_type_;

    // Indicates whether this VideoCaptureBufferTracker is currently referenced by
    // the producer.
    bool held_by_producer_;

    // Number of consumer processes which hold this VideoCaptureBufferTracker.
    int consumer_hold_count_;

    int frame_feedback_id_;
};

} // namespace content

#endif // MEDIA_CAPTURE_VIDEO_VIDEO_CAPTURE_BUFFER_TRACKER_H_
